Technical Field
The description relates to laser beam control.
One or more embodiments may facilitate protecting photon-damageable objects, e.g., the human eye, from the beam of a laser system, e.g., a Light Detection and Ranging (LIDAR) system, for instance in automotive applications.
Description of the Related Art
LIDAR systems are increasingly playing a role in certain sectors such as, e.g., the automotive field.
Being able to facilitate protection of the eyes or other damageable objects may thus represent an interesting feature when using, e.g., LIDAR systems: vehicles and cars are often in close proximity with living beings (e.g., humans and animals) which may be affected by a LIDAR beam.
A common approach for facilitating protection is based on maintaining an “eye safe” power level. This may prevent an undesired exposure of living beings with the disadvantage of sacrificing detection range: the farthest possible distance detectable by a LIDAR is related to the beam (e.g., peak) power. Examples of possible distance-to-power relationships are given in the following table.
Distance [m]1157533103.3Peak Power [W]18076151.360.15
Another common approach may involve replacing visible light, e.g., with a wavelength around 600 nm (1 nm=10−9 m), with non-visible light, e.g., with wavelengths of around 1500 nm (nm=10−9 m). These longer wavelengths may have the advantage of being non-focusable by the eye, which may be effective in preventing any damage, while having the disadvantage of using appropriate photoreceptors for such wavelengths which are less sensitive.
To sum up, common approaches, e.g., in LIDAR systems may be unable to provide a high range and a high accuracy, due to an inherent tradeoff between the power used to scan the scene and the accuracy of the estimated depth.